On the Minimum Delay Peer-to-Peer Video Streaming: How Realtime Can It Be?

P2P systems exploit the uploading bandwidth of individual peers to distribute content at low server cost. While the P2P bandwidth sharing design is very efficient for bandwidth sensitive applications, it imposes a fundamental performance constraint for delay sensitive applications: the uploading bandwidth of a peer cannot be utilized to upload a piece of content until it completes the download of that content. This constraint sets up a limit on how fast a piece of content can be disseminated to all peers in a P2P system. This paper theoretically studies the impact of this inherent delay constraint and derives the minimum delay bounds for realtime P2P streaming systems.